The invention disclosed relates to a method and apparatus of transferring randomly conveyed commodities from one location to another and distancing them one from the next at a regular, prescibed interval.
More exactly, the invention consists in a method and apparatus of transferring packs of cigarettes from the runout of a packaging machine to the entry line of a unit which envelops them in outer wrappers or cellophane.
In conventional systems, packs of cigarettes run out from a packaging machine on a continuously driven conveyor, and on reaching the end of this conveyor, are transferred onto a second conveyor, the infeed conveyor of a cellophane wrapping unit. The packs move along the first conveyor in random succession, but must be supplied to the cellophane wrapping unit in regular sequence, precisely synchronized with the movements of the unit's working parts. Accordingly, in passing from one conveyor to the other (the two are generally disposed at right angles), the packs must also be spaced apart at a given distance one from the next.
Conventionally, this operation is effected in the following manner: the far extremity of the runout conveyor incorporates a fixed stop against which a string of packs is allowed to accumulate, one in contact with the next; an actuator, made to reciprocate at the same tempo as that to which the operation of the cellophane wrapping unit is geared, impinges on the packs nearest the stop singly and in turn, transferring them to the infeed conveyor.
To ensure that the packs of cigarettes will not jump when coming up against the stop, and that the string accumulates neately and correctly, the surface of the first conveyor possesses a high coefficient of friction; in addition, the conveyor operates in conjunction with a plate that overrides the endmost part nearest the stop and is positioned so that the packs of cigarettes remain sandwiched between it and the conveyor.
With this type of arrangement, packs awaiting transfer alongside the stop become subject to damage caused by rubbing contact with the surface of the conveyor, which, it will be remembered, is embodied with a high coefficient of friction.
Moreover, following each transfer stroke effected by the actuator, the entire string of packs surges forward and strikes against the stop, occasioning a shock which not only is a cause of damage to those packs nearest the stop, which become crushed, but also, is rebounded back through the entire string. Needless to say, for each pack making up the string accumulating at the stop, this shock rebound will be repeated, and repeated as many times as there are steps separating the pack from its ultimate transfer to the second conveyor.
Accordingly, the object of the invention is to set forth a method of transferring commodities from a first conveyor to a second conveyor, ordering them at one and the same moment into a regularly spaced succession, which is able to overcome the various drawbacks besetting the prior art method described above.